Friction shock-absorbing mechanism



March 27, 1928. 1,663,994

l J. F. OCONNOR FRIcTIoN saocx AsoRBING uBcHANIsu originawilea oct. 1.1924 2 sums-snm y@ i@ M J. OV wd Patented Mar. 27, 192

UNITED STATES PATENT: OFFICE.

JOHN F. OCONNOR, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,TO W. H. MINEILINC., A CORPORATION OF DELAWARE.

FRICTION SHOCK-ABSOB-BING MECHANISM,

Application filed October 1, 1924, Serial No. 740,933. RenewedV November28, 1927.

This invention relates to improvements in friction shock absorbingmechanisms. n

One object of the invention is to provide a 'friction shock absorbingmechanism of high capacity, adapted for railway draft riggings, havinginitial spring action during which the spring resistance elements arepartly compressed, and added relatively higher capacity during theremainder of the compression stroke, due to added resistance offered bywedge friction systems, and` addr tional compression of the springresistance.

Another object of the invention is to provide a friction shock absorbingmechanism of the character indicated, of the double ended type,includingl a Heating cylindrical friction shell having interior frictionsurfaces with which cooperate a plurality of Iets o l.' friction wedgeshoes adapted to be moved upon relative appoach of the main followers,`and tandem arranged spring means coacting witlr the main followers andwedge means cooperating with'the friction shoes.

further object of the invention is to provide a friction shock absorbingmechanism, including spring resistance elements, the arrangement beingsuch that after each compression stroke,` the springs are availableindependently of the release of the friction mechanism to return themain followers to normal position and absorb subsequent shocks.

Other objects and advantages of the invention will more clearly andfully appear from the description and claims hereinafter following.

In the drawings forming a part of this rmecification, Figure l is alongitudinal, horizontal. sectional view of a railway draft rigging.showing my improvements in connection therewith. Figures 2 and 3 aretransverse. vert-ical, sectional views of the shock absorbing mechanismproper, correspending respectively to the lines 2-2and 3 3 of Figure l.Figure Ll is a detailed, perspective view of one ot' the wedge frictionshoes employed in connection with my improved mechanism.

In said drawings, -10 denote the usual channel-shaped center or draftsills of a railway car nnderframe, to the innerfaces of which aresecured front stop lugs 1l and rear stop lugs l2. The inner end portionof the drawbar is indicated at 13, to which is operatively connected ahooded yoke 14- of well-known form. Disposed within the yoke is theshock absorbing' mechanism proper, including a front follower l5 and arear follower 1G. The movable parts of the draft rigging areopcratiif'ely supported by a detachable saddle plate Yli'. The mechanismherein illustrated is of that type compris ing a cylindrical frictionshell and in order to maintain the shell properly centered, guidememlgiers vlit-1S are provided at oppo site sides of the same, the guidemembers being suitably secured to the inner faces of the draft sills.

The in'iprovcd shock absorbing mechanism proper, comprises broadly,front and rear follower acting casings A-Az a centrally disposedfloating friction shell B; front and rear wedge acting spring. followersCfG;

two pairs of wedge friction shoes Df-D; tandem arranged spring resistantelements E-E; and a retainer bolt F The front and rear follower casingsA are of like constriui'tion. Each casing A is in the form of acylindrical shell ope-n at its inner end and provided with thetransverse wall 19 at its outer cud. the wall 'i9 bearing on the innerface of the corresponding main follower and being extended laterallybeyond the outer surface of the shell to provide au annular flange 20which cooperates with the corresponding end of the friction shell tolimit the inward movement of the follower. On the inner side of the endwall l5) is provided an inwardly projecting hol' low boss 21, for apurpose hereinafter-described. e

The friction shell B, which is also of cylindrical form is open at itsopposite ends and is adapted to tclescopically receive the cylindricalshell portions of the members A. Midway between the ends of the shell Bare provided two sets of opposed, interior, cylindrical frictionsurfaces Q2-22 and 23e-23, the friction surfaces 22 and 23 being curvedtransversely ofthe mechanism. The opposed friction surfaces 22 convergeslightly forwardly of the mechauisn'i, while the opposed frictionsurfaces 23 converge rearwardly thereof. The parts are so'proportionedthat the flanges 2() of the front and rear follower, casings are adaptedto engage the opposite ends of the respective follower casings when themechanism is fully compressed and` cause the actuating force to betranslfnitted directly through the follower easings and the shell B totiheeorresponding stop lugs.

The four vfriction shoes D are all 4of like construction, and arearranged in a .circula-r.

series, one pair of opposed shoes cooperate ing with the shell frictionVsnriiiees 22 and the other pair cooperating with the shell frictionsurfaces 23. Each `shoe l) yhas a. curved outer friction surface 24adapted to cooperate with vone of the curved interior friction surfacesof the'friction 4shell A. @n the inner side, rthat is, 'the sidenearestthe 'axis Aof the 'inechanisim cach .shoe has a lateralprojection 25 provided with front and rear Wedge faces 26 and 27. Eachshoe also has an Aoutwardly projecting, 'lateral flange 28 atone `endthereof, for a kpurpose hereinafter described. The opposed .shoes Whichcooperate with the friction surfaces '22 have the flanged ends thereofforvardly disposed, VWhile the shoes coope atin with the frictionsurfaces 23 have kthe flanged Aends thereof rearwardly disposed. As.clearly show-n in l Figures l, Qnnd '3, the inner `wall of the fric-`tion shell is provided with ltwo sets of op posed recesses 29-29adapted 'lo respectively accommodate `the flanges 28 of the pairs ofshoes l). The recesses 29 coactinpv with the 'flanges 28 Iof the shoesengaging the friction surface 22 being located at :the forward end ofsaid friction surfaces, providing* inner shoulders `30 adapted tocooperate with the flanges of Vsaid shoes -to limit the rearwardmovement thereof. The openings Y29 which accommodate ftlhe flanges 28 ofthe remaining pair of shoes are disposed at the rear ends of thefriction surfaces 23 at the top and bottom `of 'the shell. The inner endrWalls of the last 'named openings also provide stop shoulders 30 whichcoopera-te with the flanges 28 -offf the last named pai'r of `shoes D Tolim-ift 'their forwird movement.

As clearly shown lin 4lllhignre l, in the inormail full release'position of the parts, tlhe in- 4ner 'end of 'the front shell A -isnt-)rina'lly slightly spaced from the front ends of `the 'friet-ionshoes iD "which cooperate with the friet-ion surfaces 23 Iand the frontVend of Vthe `rear shell A is similarly :spaced from Athe rea-r ends ofthe friction shoes 'D cooperfa-tiing with the lfriction 4surfaces 22,thereby provvielin-,e for limited relative lmovement of the followershells A with reference to the "friction shell B heitere the shoes areactually engaged and lmoved by -sairl followers.

'The spring followers "Cf-1C are of like construction, each heme' in theform of a cap haring; one stop of opposed Wedge faces niraintain, Athemechanism of un.

ment of tilre wc to Figures l, 2 and 3, it will he yseen that the 'Wedgefaces 126 Aof the front spring follower member C cooperate with thefriction shoes vD which engage the friction surfaces 22 of itheshell andthat the faces l27 of the rear spring follower C hear on the faces 27.of `theseslioes when the mechanism is in nor- `sets `of springs, ,eachspringeomnising an outer relativelT heavy coil havingits opposite'endsVhearingv respectively on the aVall l5) of the correspending'` followermember il and the outer end of the corresponding 'spring follower, andan inner, relatively light coil having the outer end `hearing on theboss 2l of the corr fponding follower and Vits Vinner end sea-ted withinthe recess of the corresponding` cup-shaped spring' fols lower.

The -r-'etainer holt ll has its front and rear `ends respectively`anchmefl within the liollow bosses of the front and rear follmrer.casings A. 'The shanlrof the holt extends through aligned openingsprovided in the spring,y followers (l. The holt serres to rui, overalland lengt-h -and holds the vparte assembled under initial compression.

As vWea-r occurs on vthe various friction and wed-ge faces,componer-.tion theref .is lpznl. due lto the expansive action of thefront and rear `sets of springs, lwl'riell as hei-einliefern pointedgout irre under initial compression, suitahleolearanee being;- leftbetween the in- 'ner ends Vof the front and rear spring follow-ermembers for this purpose.

The operation of the mechanism, asslmh yi-np; in inward Aor bnfl'ingmovement of the rlrawlmr, is as il'ollows. Ils (Erzieher movesrearwardly, 'the front follower lo and the correspondine4 casing); .Ilare l'orfefrl rearnarrllv also. compress' i* *front april resistance Ebetween ther .i the fw i spring follower C which has its rivera-fn."jino-vement limited hv en rement with eorrespoi'idino,v pair of ne ille28. Due to the floating' :irra nent il' the friction shell l, the rearspr nient/her E Will he si multaneoos t hetween the ivafll 19 `of the Y.shell A. and the rear spriue pleur her C, -th f' aftter ylieine "fo'rcrlrerwraril'li unison y-u'ith the :friction shell lia' en' 'e faces 2G ofthe cor spondingg oa'n" `or friction wedge elio-vs with the wedge faces126. lt Will he evident that the pair-of `Wedge friction shoeA lest rterri-d klilo to is forced rearwardly with the shell, due to engagementof the flanges 28V thereof with the rear shoulders 30.

As will be evident, during thefinitial 'action just described, therewill be no relative movement of the shell and friction shoes, thecompression of the n'lechanisn'i merely effecting compression of thetandem 'arranged springs. As the described actioncontinues, the innerend of the front follower shell A will gradually approach the outer endsof the friction shoes of the corresponding pair, while the rear ends ofthe remaining friction shoes will approach the front cud of the rearfollower shell. This actioncontinues until the front and rear followershells engage the corresponding friction shoes, whereupon the two pairsof shoes will be moved relatively to each other and relatively to thefriction shell, thereby offering additional resistance to therelativemovement of the followers. At the same time, as well as duringthe initial. action of the mechanism, a wedging action will be set upbetween the Arespective spring followersrand the corresponding frictionshoes, pressing the shoes against the friction surfaces of the shell. Asthe shoes are moved by the respective followers, the front and rearspring followers will be forced apart, each spring follower carrying apair of shoes on faces 126, only, the faces 127 having no function afterinitial movement of the shoes, and due tothe converging relation of theopposed friction surfaces of the shell, va differential wedge actionwill be set up, causing the spring followers to move at a greater speedthan the corresponding pair of friction shoes, thus effecting additionalcompression of the spring resistance elements. Movement of the partswill finally be limited by engagement of the flanges of the fronty andrear follower acting shells with the opposite ends of the frictionshell, whereupon the pressure will be transmitted directly through theseparts to the rear follower, as

hereinbefore pointed out.

It will be seen that the resistance during the last described portion ofthe compression stroke is greatly increased over that had during theinitial action of the mechanism. inasmuch as each set of springs iscompressed from both ends, and that to thev resistance thus offered isadded the frictional resistance between the various shoes D and thefriction surfaces of the shell.

Upon reduction of the actuating force. the springs E act to immediatelyforce the shells A apart. As the shells are moved out of engagement withthe corresponding friction shoes D, the wedging pressure is materiallyreduced, thereby permitting the springs to restore the pairs of shoes,the front and rear spring followers and the shell A to normal position.As will be evident, the restoration sistance elements would still beavailable to absorb the next succeeding shock to which the mechanism issubjected, and at full capacity.

I have herein shown and I no\v consider the preferred manner of arryingout my invention, but the same is merely illustrative and I contemplateall changes and modifications that come within the scope of the claimsappended hereto.

I claim:

l. In a friction shock absorbing mechanism, the combination with frontand rear follower acting members, relatively movable toward and awayfrom each other; of tandem arranged spring resistance elementsinterposed between said follower-acting members, a plurality oflongitudinally disposed, relatively movable friction shoes interposedbetween said springs, certain of said shoes cooperating with one of saidfollower-acting members to be moved thereby during the compressionstroke, and the remaining shoes cooperating with the otherfollower-acting member to be moved thereby during said compressionstroke; a frietion shell having curved interior friction surfaces withwhich said shoes cooperate and means for pressing said shoes againstsaid surlaccs, said means including a pair of relatively movable lateralwedge pressure creating members adapted to be resisted by the respectivespring resistance elements.

2. In a friction shock absorbing mechanism, the combination with frontand rear followers relatively movable toward and away from each other:of tandem arranged springs interposed between said followers: and meansinterposed between said springs, actuated by the relative movement ofsaid followers for forcing` said springs apart, said means including alongitudinally disposed friction element. relatively movable frictionshoes adapted to be actuated respectively by said followers andcooperating with said friction element, and wedge elements cooperatingwith said springs.

3. In a friction shock absorbing mechanism, the combination with frontand rear followers relatively movable toward and away from each other;of spring resistance elements interposed between said followers. one ofsaid spring elements being associated with each follower; a wedgefriction shoe coacting with each follower; a wedge pressure transmittingmember coacting with each shoe, and adapted to be moved by the latterupon relative movement of the front and rear followers to apply pressureto the inner ends of said tandem springs; and a described what lateralpressure resisting member having friction :surfaces cooperating `withsaid shoes. V

lf. ln ra friction sliock 'absorbing mechanism, the combination withfront and rear followers; of a 'friction shell interposed between saidfollowers, said shell having two sets of longitudinally disposed,opposed, interior friction surfaces; friction means interposed betweensaid followers, said vmeans including wedge a'nei'nbers, and a pair offriction slices coacting with each ftollonfer and fone of said wedgeniernhers, said pairs of shoes coacting respectively with the tivo setsof shell friction surfaces; and yielding, movement-resisting meansinterposed between each wedge member and one of the follow-ers.

`5. In a friction shock absorbing mechanism, 4the combi-nation withfront and rear :follower acting ineens; of a :cylindrical frictionyshell interposed between said follower- 'actinga means, said shellhaving; two sets vof opposed, `longitudinally arranged, interiorfrictionsurfaces, lone set of said surfaces converging 'rearwardly :ofthe mechanism and the other `set converging `forwardly of saidmechanism; front and rear pairs of Wedge friction :shoes :cooperatingwith the respective sets `of friction shell surfaces and adapted to lbeactuated by said.follower-acting,means; front and rear wedgescooperating with said shoes; and front and rear spring' resistanceelements cooperating with the respect-ive wedges.

6. :In .a friction shoclr'(rbsorbing` mechanism, the combination withfront land rear follower acting means; of a friction shell interposedbetween 'said follower acting means, said shell having 'its oppositeends normally spaced from the respective follower-actingineans andbeing` further `provided with interior, friction surfaces arranged inoppositely converging pairs; front and rear pairs of friction shoescooperating with the respective pairs of friction surfaces ofthe shell,said pairs of shoes being' adapted to be actuated 'by the respectivefollower-acting means, said shoes being normally spaced from saidfollower-acting` means to permit of preliminary action of the mechanism;front and rear wedges cooperating` cwith said shoes; and front and 'rearspring tesis 'ance `elements cooperating with the respective wedges.

' ,'YJIn wa' friction shock absorbing mecha- ;nism, the conibina-tionwith front and rear follower acting means; of `a friction shellinterposed between said follower-acting means, said shell having aplurality of longitudinally disposed, interior, curved frictionsurfaces; two sets of friction slices cooperating` with the shellfriction surfaces and adapted tobe actuated by saidfollower-acting-means during,` compression of the mechanism; a wedgeengaging each set of friction shoes; and tandem arranged springsinterposed between said follower-acting means and cooperating with saidwedges.

8. In a friction shock absorbing; mechanism, the ycombination with frontand rear follower acting means; of a friction shell interposed betweensaid follower acting means, said shell having a ypln-.iality oflongitudinally disposed, interior friction surfaces; tandem arrangedsprings interposed between said follower-acting' `:1n-cans, a spring`follow-er cooperating with each springeach of said spring followershaving wedge faces; two sets of friction wedge shoes cooperating withthe wedge faces of said spring` fol,- lowcrs; and means fortranemitting` lthe actuating force from each follower acting Vmeans toone of said sets of friction wedge shoes.

9. In a frictionl shook beer-hint,T mechanism, `the combination withfront and rear follower acting shells; a friction shell interposedbetween said follower acting;- shells and adapted to -telescopicallyreceive the inner ends thereof, said friction shell having interiorfriction surfaces; a plurality of friction wedge shoes within `thefriction shell cooperating `withthe fric-tion surfaces thereof, said:shoes bein-g arranged in sets, one set being adapted to be moved by thefront follower sli-ell and the other set by the rear follower shell;spring followers having wedge faces coacti-ngwith the respective sets ofshoes; a spring resistaiiee interposed between each follower' shellvand. spring fol-- lower; and coacting means on the shoes and frictionshell for lim-it movement of each 'set yof shoes lwith*reference to thefriction shell `in one direction.

In. witness that I claim the foregoing I have hereunto subscribed mynaine this Qith day fof September, 1924;. i

JOHN F, UCONNOR.

